I guess that nobody knows the secret to this. I thought for sure somebody would have cracked all the secret settings in the head unit 
I think this is an issue regardless if you leverage your own personal Internet connection via bluetooth or the in-car Verizon Wireless 3G radio built into all of the cars. (I don't know at what point Verizon deactivates the phone/modem, if ever, assuming MBrace is not active.)A big concern with doing this would be the attack vector it presents to all CANBUS systems.
See:
< http://www.slkworld.com/off-topic/262114-hackers-could-control-your-car.html > and
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